US President Donald Trump has defended his eldest son over a meeting with a Russian lawyer last year, declaring on Twitter that he is "open, transparent and innocent".
The comments came a day after Donald Trump Jr revealed his eagerness to hear damaging information about Hillary Clinton from the Russian government in a meeting with the lawyer from Moscow during the presidential campaign.
Defending his son's conduct, the president again dismissed the ongoing Russia investigation as the "greatest Witch Hunt in political history".
Mr Trump responded after Mr Trump Jr disclosed a series of emails on Tuesday that marked the clearest sign to date that Mr Trump's campaign was willing to consider election help from a long-time US adversary.
The email exchange posted to Twitter by Mr Trump Jr showed him conversing with a music publicist who wanted him to meet with a "Russian government attorney" who supposedly had dirt on Mrs Clinton as "part of Russia and its government's support for Mr Trump".
The messages reveal that Mr Trump Jr was told the Russian government had information that could "incriminate" Mrs Clinton and her dealings with Russia.
"I love it," Mr Trump Jr said in one email response.
The president's lawyer, Jay Sekulow, said in an interview with NBC's Today that Mr Trump Jr did not violate any laws by accepting the meeting.
He said the president had not been aware of Mr Trump Jr's June 2016 meeting and did not find out about his son's email exchange until "very recently".
Mr Sekulow said the president was not being investigated by former FBI director Robert Mueller, the special counsel investigating the Trump campaign and its interaction with Russia during the election.
"I would know a little bit about it. I'm one of the lawyers," Mr Sekulow told ABC's Good Morning America.
As the emails reverberated across the political world, Mr Trump Jr defended his actions in an interview with Fox News, blaming the decision to take the meeting on the "million miles per hour" pace of a presidential campaign and his suspicion that the lawyer might have information about "under-reported" scandals involving Mrs Clinton.
He said the meeting "really went nowhere" and that he never told his father about it because there was "nothing to tell".
"In retrospect I probably would have done things a little differently," Mr Trump Jr said.
Democrats in Congress voiced outrage and insisted the messages showed clear collusion, with California Representative. Adam Schiff, the top Democrat on the House intelligence committee, declaring that "all of the campaign's previous denials obviously now have to be viewed in a different context".
Yet Republicans - who stand the most to lose politically from Mr Trump's Russia ordeal - did not join in the condemnation.
Senate Majority Leader Mitch McConnell said he was confident Senate investigators would "get to the bottom of whatever happened".
And Senator Susan Collins, a Maine Republican on the intelligence committee, cautioned that the emails were "only part of the picture".
Mr Trump Jr, who was deeply involved in his father's presidential campaign, portrayed his decision to release the emails as an effort "to be totally transparent".
In fact, they had already been obtained by The New York Times.
Hours after the son posted the emails, the father rose to his defence.
"My son is a high-quality person and I applaud his transparency," the president said in a statement read to reporters by White House spokeswoman Sarah Huckabee Sanders.
Although Ms Sanders declined to answer questions about the emails, she stood by the White House's long-standing insistence that no one in Mr Trump's campaign colluded to influence the election.
The messages were the latest disclosure to roil the multiple, ongoing investigations into Russia's interference in the election and potential collusion with Mr Trump's campaign.
US intelligence agencies have said the Russian government meddled in the election through hacking to aid Mr Trump.
The emails will almost certainly be reviewed for any signs of co-ordination with the Kremlin, which the White House and Mr Trump Jr have repeatedly said did not take place.
A spokesman for Mr Mueller declined to comment.